...

The generator's flowrate history

, generator's wellbore pressure history

and receiver's wellbore pressure history

are assumed to be known for the whole period of the test.

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The pressure trends at generator

and receiver

may have unknown origin but in order for

decomposition to work they should have minimum correlation with generating well

pressure flowrate variation

. In terms of spectral analysis this means that

pressure trend

's spectrum contains minimum overlap with spectrum of

pressure flowrate variation

at generator.

The contamination components of the trends should either have This particularly means that pressure trends at generating and receiving wells may contain:

- low frequencies (created by monotonous

...

- activities of distant wells), which are lower than frequency range of the generating well flow variation

or

- high frequencies (created by lift instability at generating/receiving well), which are higher than frequency range of the generating well flow variation

If pressure .If for some reasons the trends contain components correlated with

(for example receiving well or distant wells have been synchronously varying the rates with generating well) then

decomposition is not unique and should not be considered.

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